Heat Pump question

[livetohunt]

Lately my heat pump has been running almost all the time..It will blow warm air and heat to the temp set on the thermostat, then it will blow cool or room temp air out until it needs heat again. Outside the unit runs continuously. If I switch it to emergency heat it will operate normally, heating until reaching the temp set on thermostat and then shutting down. Any ideas?

 

[Bigtimber]

Sounds about like what mine does....

 

[Milkman]

Do you have the fan on run or auto?

 

[Jeepnfish]

Heat pumps struggle when the temps are 35 or lower. I run aux heat till the temps come back up.

 

[livetohunt]

Do you have the fan on run or auto?

Auto and the unit does this even if temps are in the 40s or even 50s.. Once the unit comes above the temp set on thermostat it shuts off, but it seems like the unit just maintains the temp set and never comes above it. If I move the temp set on thermostat from say 65 to 68, it will heat it to 68 then just run continuously and maintain 68.

 

[Milkman]

The fan should shutoff when the heat pump reaches set point.

 

[baddave]

the timer on the pc is set to a determined time .say 30 seconds . the fan will run for 30 seconds after the tstat is satisfied and the compressor stops.. i would bet the pc board w/ the timer contacter is gone.. usually replace the pc board

 

[livetohunt]

the timer on the pc is set to a determined time .say 30 seconds . the fan will run for 30 seconds after the tstat is satisfied and the compressor stops.. i would bet the pc board w/ the timer contacter is gone.. usually replace the pc board

Ok, I'll check into that but it will shut down once thermostat temp goes above the set temp..Like when it warms up a lot during the day. Otherwise it seems like the unit runs all the time just to maintain that set temp..I'd say 75% of the time it blows cool air or room temp air out though.

 

[Milkman]

Is your outside coil clean? Does someone do routine maintenance?

 

[baddave]

Ok, I'll check into that but it will shut down once thermostat temp goes above the set temp..Like when it warms up a lot during the day. Otherwise it seems like the unit runs all the time just to maintain that set temp..I'd say 75% of the time it blows cool air or room temp air out though.

good luck finding the right board and purchasing it . I would recommend call someone , it probably will not be that expensive . service call and the board , i would expect less than $300. but don't hold me to that . good luck

 

[livetohunt]

Is your outside coil clean? Does someone do routine maintenance?

I had some work done on it last year for something else but no routine maint..

 

[livetohunt]

good luck finding the right board and purchasing it . I would recommend call someone , it probably will not be that expensive . service call and the board , i would expect less than $300. but don't hold me to that . good luck

Thanks

 

[Oldstick]

Is your outside coil clean? Does someone do routine maintenance?

Agree with this. But also it could be the normal defrost cycle for heat pumps during very cold temps like we have had this past week. That means the heat pump reverts to summer AC mode for a few minutes to heat up the outside coils and melt the ice build up that is unavoidable during very cold weather on heat mode. On some models the inside furnace fan stops running during this brief cycle, but on others the fan continues to run blowing cold summer AC air out into the house for a few minutes until the outside defrost is complete.

When you think it is happening go outside and listen for the change in cycles. That will tell you if this is what is happening.

 

[Oldstick]

Or low on freon is another possibility.

 

[livetohunt]

Agree with this. But also it could be the normal defrost cycle for heat pumps during very cold temps like we have had this past week. That means the heat pump reverts to summer AC mode for a few minutes to heat up the outside coils and melt the ice build up that is unavoidable during very cold weather on heat mode. On some models the inside furnace fan stops running during this brief cycle, but on others the fan continues to run blowing cold summer AC air out into the house for a few minutes until the outside defrost is complete.

When you think it is happening go outside and listen for the change in cycles. That will tell you if this is what is happening.

Mine goes thru this cycle when its cold outside and the fan stops on the outside unit..In this case, it is not the problem.

 

[Lukikus2]

Or low on freon is another possibility.

Agree. Check the freon first. Make sure the insulation is still good on the lineset also.

 

[Oldstick]

Mine goes thru this cycle when its cold outside and the fan stops on the outside unit..In this case, it is not the problem.

Understand. Most of them stop the fan on the outside when in the defrost cycle. But I have experienced units that keep blowing the inside fan for a few minutes while on defrost. Just as if the inside furnace fan thinks the heat coils are still running, but actually it is blowing cold air for a few minutes during the defrost. Just checking to see if that is what is happening.

 

[livetohunt]

Understand. Most of them stop the fan on the outside when in the defrost cycle. But I have experienced units that keep blowing the inside fan for a few minutes while on defrost. Just as if the inside furnace fan thinks the heat coils are still running, but actually it is blowing cold air for a few minutes during the defrost. Just checking to see if that is what is happening.

Yes I have seen that happen when going thru the defrost cycle in the past..Now mine will blow cool air for long periods not during a defrost cycle.

 

[Milkman]

The outside coil may be covered in grass clippings, etc. You can tell by looking through the outside grill type covers

 

[bulletbob]

Just use the unit in aux heat.That is the same as having an electric furnace.Anything below 40 degrees ,you are not going to get any heat from the heat pump anyway.